Fig. 3.

Estimated numbers of neuronal somata per hemisegment in Onychophora (Euperipatoides rowelli) as revealed by different markers. The upper left diagram shows the general organisation of a single ventral nerve cord in dorsal view (median is up) from one body side and two consecutive leg-bearing regions. To estimate the number of neuronal somata, the region of a nerve cord corresponding to a hemisegment (light blue) was subdivided into 10 equal regions (I–X), in which the somata were counted. Each hemisegment was defined by two consecutive anterior leg nerves (al1 and al2). Bar graphs illustrate the counted numbers of labelled somata as identified by different antisera in corresponding regions of the nerve cord displayed below each diagram. Note that the number of cell bodies stained with a DNA-selective marker was estimated by using sections from the regions indicated by bar graphs. Anti-RFamide-like immunoreactive cell bodies were categorised in small (light blue) and large cell bodies (dark blue). Note also that only one specimen was analysed for each marker. al1 and al2, anterior leg nerve 1 and 2; le1 and le2, leg nerve 1 and 2; mc, median commissure; rc, ring commissure; pl1 and pl2, posterior leg nerve 1 and 2